Arrangement in magnetic recorders having a trick switch



March 1, 1966 v. POLLASCHEK ARRANGEMENT IN MAGNETIC RECORDERS HAVING A TRICK SWITCH Filed Aug. 51, 1960 INVENTOR VIKTOR POLLASCHEK AGENT United States Patent 3,238,308 ARRANGEMENT IN MAGNETIC RECORDERS HAVING A TRICK SWITCH Viktor Pollaschek, Vienna, Austria, assignor to North American Philips Company, Inc., New York, N.Y., a corporation of Delaware Filed Aug. 31, 1960, Ser. No. 53,239 Claims priority, application Austria, Sept. 4, 1959, A 6,420/59 2 Claims. (Cl. 179-1002) This invention relates to arrangements in magnetic recorder machines having a trick switch.

If, on an existing magnetic recording, a further recording must be superimposed (trick record), it is necessary for the erasing action of the erasing head to be eliminated substantially. For this purpose, the erasing current in the erasing head may be either attenuated or interrupted completely, or the sound carrier and the erasing head may be spaced apart a certain distance. The member for carrying out the electrical and mechanical changes is herein referred to as a trick switch. As long as the trick switch is in an on position, normal records cannot, of "course, be made. After termination of a trick record it is quite possible to turn ofi the trick switch, thus such switches have been designed, for example, in the form of a key which upon release returns to the rest or off position of its own accord. However, such a switch is inconvenient, since it must be held in the on position during the whole trick recording. This invention relates to a convenient arrangement safeguarded against erroneous operation in normal recording and in which a trick switch is freely movea'ble of itself, and is also automatically switched off by the recording switch controlling operation of such machines.

According to the invention, a driving element is provided which co-acts with the mechanism of the recording switch and which is brought into unilaterally active connection with a slideable trick switch. The trick switch can thus be manually operated freely upon switching on the recording operation, but is switched 01f and held in a constrained manner upon discontinuing recording, i.e., switching off recording operation.

The embodiment according to the invention leaves the user complete freedom to operate the trick switch at will to its on or off position when the machine is set for recording by means of the recording switch. It thus provides complete security that each record is started with the trick switch in the off position and hence under the correct conditions for recording. This effect is also obtained with a minimum use of mechanical means.

In order that the invention may be readily understood and carried into effect, it will now be described in detail, by way of example, with reference to the accompanying diagrammatic drawing which shows only one embodiment thereof without intending to be limited thereto.

Turning the recording operation off or on is accomplished by means of a key (not shown), a switching rod 1 which is shown in the rest position and thus the recording operation is turned off. The members to be operated by the key, such as sets of contacts, etc. are not shown. To turn on the machine for recording, the rod 1 must be moved in the direction indicated by the arrow 2. The rod 1 is then arrested by means of a lug 3 in known manner by a locking member 4 which is pivotal about axis 5 and which is maintained in contact with the switching rod 1 by means of a spring 6. Secured to the rod 1 is a Bowden cable 7 which is maintained stretched by a spring 8. The Bowden cable 7 has a driving element 9 secured to it. The trick switch 10 is preferably of the slidable type for simplicity. The contacts or the like to be operated by it are not shown, and the switch is indicated in its non-rest or operative off and on positions, i.e. the trick switch is movable by operating handle 11 of the trick switch 10. The handle 11 has an aperture 12 through which the core of the Bowden cable 7 is passed. The driving element 9 is secured to the Bowden cable 7 so as to engage the handle 11 if both the trick switch and the recording key occupy their oft positions. When the machine is turned on for recording, the rod 1 of the recording key is moved in the direction indicated by the arrow 2 until it is locked, the driving element 9 is withdrawn from the operating handle 11 so as to release the trick switch 10 for switching on and off at will. When the recording key connected with rod 1 is released or placed in its off position, the driving element 9 moves the switch 10 to its off position.

When the driving element is provided on a Bowden cable, as in the example described, the relative position of the recording switch and the trick switch can be varied greatly. As a matter of fact, instead of using a key as the recording switch, use may be made of any other switch, for example a rotary switch, the two positions of which may also be transmitted to a driving element 9 in a similar manner with the aid of a Bowden cable. In special cases, it may also be possible to place the recording switch and the trick switch in such relative positions that the driving element is positioned directly on a portion of the mechanism of the recording switch, or is integral with this mechanism.

What is claimed is:

1. An improved trick switch for a recorder/reproducer comprising an erasing means, a slidable trick switch having off and on positions operatively connected with and controlling said erasing means, a member having an off, and on position operatively connected with and controlling the recording operation of said recorder/ reprod'ucer, and means interconnecting said trick switch and said member, said means including a driving element for releasing said trick switch to permit manual movement to its 0 and on positions when said member is in its on position, and placing and holding said trick switch in its off position when said member is placed in its off position.

2. The improvement according to claim 1, wherein said means including said driving element comprises a Bowden cable having one end secured to one end of said member and having said driving element secured adjacent the other end of said Bowden cable.

References Cited by the Examiner UNITED STATES PATENTS 619,900 2/ 1899 Miller 20050.3 1,136,639 4/1915 Zimmer 20050.3 1,563,160 11/1925 Catlin 20050.3 1,564,207 12/ 1925 Cloud 200172 2,171,073 8/1939 Winning 200-161 2,557,351 6/1951 Jacobson 200-503 FOREIGN PATENTS 1,197,025 6/ 1959 France.

IRVING L. SRAGOW, Primary Examiner. MAX L. LEVY, BERNARD A. GILHEANY, Examiners. 

1. AN IMPROVED TRICK SWITCH FOR A RECORDER/REPRODUCER COMPRISING AN ERASING MEANS, A SLIDABLE TRICK SWITCH HAVING "OFF" AND "ON" POSITIONS OPERATIVELY CONNECTED WITH AND CONTROLLING SAID ERASING MEANS, A MEMBER HAVING AN "OFF," AND "ON" POSITION OPERATIVELY CONNECTED WITH AND CONTROLLING THE RECORDING OPERATION OF SAID RECORDER/ REPRODUCER, AND MEANS INTERCONNECTING SAID TRICK SWITCH AND SAID MEMBER, SAID MEANS INCLUDING A DRIVING ELEMENT FOR RELEASING SAID TRICK SWITCH TO PERMIT MANUAL MOVEMENT TO ITS "OFF" AND "ON" POSITIONS WHEN SAID MEMBER IS IN ITS "ON" POSITION, AND PLACING AND HOLDING SAID TRICK SWITCH IN ITS "OFF" POSITION WHEN SAID MEMBER IS PLACED IN ITS "OFF" POSITION. 